Process of producing articles of quartz glass.



O. C. TRAUTMANN.

PROCESS OF PRODUCING ARTICLES 0F QUARTZ GLASS. APPLICATION FILED AUG. 10. 191's.

1,215,432. Patented Feb. 13, 1917.

V @nvem-foz $3 1 album UNITED STATES PATENT OFFICE.

. OTTO C. TRAUTMAN N, OF NEW YORK, N. Y., ASSIGNOR TO SIDIO COMPANY OF'AIERICA, INQ, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

PROCESS OF PRODUCING ARTICLES OF QUARTZ GLASS.

Specification of Letters Patent. Patented Feb. 13, 1917- i Application filed August 10, 1916. (serial No. 114,104.

To all whom it may concern: Be it known that I, '1'10 C. TRAUTMANN, citizen of the United States, and a resident of New York city, in the county of New York and State of New York, have invented certain new and useful Improvements in Processes of Producing Articles of Quartz Glass, of which the following is a specification; y o This invention relates to processes of producing articles of quartz glass, particularly quartz glass tubes.

The difliculty experienced in making artieles of quartz glass has been chiefly due to l the necessity of the very rapid handling of the plastic body within certain comparatively close limits of temperature. The.

comparatively high temperature required to reduce the quartz to plasticity necessitates the use of an electric resistance furnace with a resistance core. Afterthe quartz is reduced to a plastic state, at which it can be drawn out, it has hitherto been found necessary to remove the core and then draw the :5 tube. This operation, however, is wasteful of time, and furthermore, makes it diflicult to draw the tube properly.

In my improved process, the resistance core is left within the'plastic mass while the 1 0 same is drawn, thus dispensing with the step required in previous processes'hitherto 'used. The resistance core .isbrokeninto two parts, as by a slight twist of the extremities of the core and the two portions remain in the end of the tube as the same is drawn out. Thus, notonly is a saving of time effected, but also the portions of the core serve as guides for producing aperfectly cylindrical tube, and in handling the 10 plastic mass, the ends thereof may be readily grasped "in tongs against the hardcore without fear of deforming the tube.

In the accompanying drawing illustrating diagrammatically the apparatus for carrying out my process,

Figure 1 is a sectional elevation of an electric resistance furnace showing the plastic quartz accumulated around the resistance core.

of Fig. 1.

Fig. 3 is a sectional elevation illustrating the tube as drawn out.

Fig. 2 is a section taken'along line 22 '7 part shell 10, 11, hinged together so that it may be quickly opened for discharging the surplus quartz sand, and removing the plastic. The shell may be lined with a suitable heat resisting material 12.

Closing the bottom of the furnace is a base portion 13 made of some conducting material and at the top of the furnace is a similar piece constituting a head 14 also of a conducting material. These parts 13, 14, constitute electrodes between which is disposed the resistance core 15. Current is supplied to the electrodes by any suitable connections as wires 16, 17.

The resistance core 15 is preferably clamped in the electrodes 13, 14 by suitable means such as set screws 18 having handles 1.9 extending downward for ready manipulation.

The core 15 before placed in position is preferably reduced slightly in sectionat a certain point as 20 so as to cause it to subsequently break at that point in a succeeding step in the process.

When the-core has been placed in position in the base 13 and the furnace closed (as by the latch 21 provided for that purpose), the quartz sand is introduced into the furnace, and then the head 14 is lowered over the top of the furnace by any suitable means as by tongs 22 and the core 15 is clamped in place by the set screw 18. Current is then ap lied until a suflicient mass of quartz has sed around the core. The surplus sand is thereupon emptied from the furnace, the core broken and the tube drawn out, 'This may be accomplished as follows: I v

The portions 10, 11 of the furnace may be unlatched and swung open, permitting the surplus sand to flow out, a quick twist may be imparted to the head 14, thereby breaking the core at the reduced portion 20, then the set screws 18 are loosened, freeing the ends of the core, whereupon the latter togethe 100 with the ends of the plastic mass may be graspedby suitable ton s such as 2-3and p drawn out with the portions of the core re-' maining in the extremities of the-tube, as clearly appears in Fig. 3. A suitable trough 24 may be provided near the furnace in which the tube may be readily drawn.

It will thus be seen that I have evolved a process which'efi'ects the utmost economy of time in handling the plastic. All the various steps of the process can be carried out with a minimum expenditure of time and assurance is had that e'tube' of true cylindrical form is drawn out. w

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1; The process of making quartz glass tubes consisting in heating the quartz into a plastic state in an electric resistance fur nace about a resistance core, then breaking the resistance core and grasping the core portions'and plastic and drawing the latter out into a tube with thefcore portions remaining in the ends thereof.

2. The process of making quartz lass tubes'consisting in heating the quartz in an electric resistance furnace about a resistance core, the latter being reduced in section at a point intermediate the ends thereof, then breaking the core at its reduced portion and drawing out the tube with the portions of the core remaining in the ends thereof,

3. The process of making quartz glass tubes consisting in heating the quartz into intense a plastic state in an electric resistance furnaee about a resistance core, then twisting the -end of the core so as to break the same intermediate the ends thereof, and grasping the core portions and plastic and drawing the latter out into a tube with the core portions remaining in the ends thereof.

4. The process of making quartz glass tubes consisting in heating the quartz in an electric resistance furnace about a resistance core, the latter being reduced in section at a point intermediate the ends thereof, then twisting the end of the core so as to break the same intermediate the ends thereof at its reduced portion and drawing out the tube with the portions-of the core remaining in the ends thereof.

Signed at New York city, in the county of New York and State of New York, July, A. D. 1916.

v OTTO C. TRAUTMANN.

Witnesses:

NATHAN CoHEN, D. B. KLEIN." 

